NVIDIA on Tuesday announced that the US Patent and Trademark Office (USPTO) has initially rejected 41 patent infringement claims regarding seven patents Rambus has filed against NVIDIA back in July of 2008. NVIDIA challenged these claims in November of 2008, when Rambus filed a complaint in an International Trade Commission (ITC) action. All patent infringement claims from Rambus relate to memory controllers in graphics processors.

Aside from the seven patents reviewed to date by the USPTO, two more are still pending challenge and review, though a decision regarding their validity is expected to come in the next 60 days.

"We will continue to vigorously defend this matter in the ITC," said David Shannon, NVIDIA's executive vice president and general counsel.

Rambus has been known to sue companies for alleged infringing on its patents in the past, with other targets including Hynix. More recently, Rambus was in the news when the US Federal Trade Commission dropped the antitrust case against the memory maker.